Plug-In Solar for Flat Roofs: Can We Make Garage Solar as Easy as Balcony Solar?
Plug-in solar has made small-scale solar dramatically simpler. Instead of running the solar installation as a construction project, homeowners can purchase a small set with solar panels, converters and cabling, connect it to their home and start producing their own electricity. These systems are now allowed in many countries and regions - and they have given millions of people the opportunity to generate their own clean and free energy.
These systems were originally developed for balconies, and are often called "balcony power plants" in Germany ("balkonkraftwerke"). But what if you do not have a suitable balcony?
Millions of homes have something that could be even better: a garage, extension, shed, carport or another small flat roof.
A relatively small roof can produce a useful amount of electricity. Depending on location, shading and system size, even a garage roof may be able to generate around 1,000 to 2,000 kWh per year.
The problem is that putting solar on a flat roof is still surprisingly complicated.
At Over Easy Solar, we are now exploring how we can change that. Our goal is to develop a lightweight, highly prefabricated plug-in solar solution specifically for small flat and green roofs.
Already interested? Sign up for early access.
The new product is currently under development and is not yet available for purchase. We are inviting interested homeowners to register for early access and, if they want, participate in defining what the product should become.
Your garage solar shouldn't need a construction project
Today, installing two, four or six conventional solar panels on a garage roof is not necessarily much simpler than installing a much larger solar system.
You need solar modules, a mounting system, clamps and fasteners, roof protection materials, cables, an inverter or microinverters, and often ballast. These components may come from several different manufacturers and have to work together as one system.
Then comes the engineering.
Solar panels mounted at an angle are exposed to significant lift forces from wind. On a flat roof, the system therefore has to be designed so that the panels cannot lift off during strong winds.
The conventional answer is normally ballast, mechanical fastening to the building, or a combination of both.
This creates a particular problem for small roofs. A small installation can require a surprisingly large amount of ballast relative to its size. The calculation in itself is also not simple, and it is not easy to get professional help for a small project.
The ballast adds weight to a roof that may never have been designed for a heavy solar installation. Mechanical fastening can reduce the need for ballast, but may interfere with the waterproofing of the roof.
Wind loads also depend on factors such as building height, roof dimensions, surrounding terrain and where the panels are positioned on the roof. This is real engineering, even if you are only installing a few panels.
We have written more about how wind loads affect solar installations and why vertical solar behaves differently on flat roofs.
For a professional commercial solar project, dealing with these questions makes sense. For a few panels on a garage, it creates a different problem: you normally still need a professional solar installer, and the cost of engineering, mounting and installation can become too high compared with the value of such a small system.
That is why we think small flat-roof solar needs a different approach.
Solar as a product, not a project
I founded Over Easy Solar after working in the solar industry for many years.
Solar modules had improved enormously. They had become more efficient, less expensive and extremely reliable. But I felt that the way we installed them on flat roofs was still too complex, too heavy and surprisingly old-fashioned.
The solar installation was assembled on the roof from many different components. Large panels had to be lifted into place, attached to mounting structures and secured using ballast or fastening. A significant amount of the work and cost had little to do with actually producing electricity.
So we asked a different question:
What if the entire solar installation could be designed as a single prefabricated product?
That question became Over Easy Solar.
We developed our Vertical Photovoltaic Unit, or VPV Unit, a system specifically for flat and green roofs. Instead of conventional tilted panels, our solution uses low-profile vertical solar panels in highly prefabricated units. The design eliminates uplift wind forces and allows installations to be lightweight, normally without heavy ballast or roof penetrations. Our current commercial system weighs around 12 kg/m².
Since starting the company, we have moved from prototypes to commercial installations across multiple countries. Over Easy Solar systems have now been installed across tens of thousands of square metres of flat rooftops.
We started by solving the problem for large roofs. Now we want to see if we can solve it for small ones.
Can flat-roof solar become genuinely DIY?
Our new plug-in project starts from a simple idea: combine what we have learned about lightweight flat-roof solar with the simplicity that has made plug-in and balcony solar successful.
We are not simply trying to make a smaller version of our existing commercial product.
We are asking what the ideal product would look like if it were designed from the beginning for a garage, extension, shed or other small flat roof.
Our current design goals are straightforward:
Highly prefabricated: as much assembly as possible should happen before the product reaches your roof.
Lightweight: avoid carrying large amounts of concrete ballast onto a garage.
No roof penetrations: the installation should not require drilling through a waterproof roof.
Engineered for low wind forces: wind should be addressed through the product design, rather than simply adding more weight afterwards.
Few components: modules, mounting and electrical components should form one coherent system.
Simple to assemble: installation should not require specialist solar mounting experience.
Plug-in where regulations allow: microinverter technology can potentially remove the need for conventional electrical installation in markets where plug-in solar is permitted.
Designed to look good: a small solar system next to your home should look like a finished product, not a miniature industrial construction site.
These are development goals, not the specifications of a finished product. Some will change as we test the concept, understand regulatory requirements and, importantly, talk to potential users.
Help us design plug-in solar for flat roofs
Our spirit has always been to involve the users in product development from day one. One of the reasons we are talking about the concept before the product is finished is that we want to understand what people actually need, and how many might be looking for a simple flat roof solar system like this.
Would you install solar yourself? How large is your roof? Would maintenance concern you? What about wind, electrical safety, appearance or installation complexity? Would you want a battery, or would a simple grid-connected system be enough?
We would rather ask these questions now than develop a finished product and discover afterwards that we solved the wrong problems.
If you have a garage, extension, shed, carport or another small flat or green roof, you can register for early access on our plug-in solar page.
If you want, you can also tell us more about your roof, your needs and your concerns. That input will become part of our design process as we work towards a new generation of small-scale flat-roof solar.
This project is financed by DIP-DOGA under the project number DIP2026-175409. The project has also been featured by Byggfakta, Bygg.no, Energiaktuelt and Shifter.
